1. Technical Field
The present invention generally relates to communications between computer systems and more particularly with how a System Area Network (SAN) like InfiniBand Reliable Datagram Queue Pairs (RD QPs) can be associated with one or more End-to-End Contexts at the local host channel adapter.
2. Description of Related Art
In a System Area Network (SAN), the hardware provides a message passing mechanism which can be used for Input/Output devices (I/O) and interprocess communications between general computing nodes (IPC). Consumers access SAN message passing hardware by posting send/receive messages to send/receive work queues on a SAN channel adapter (CA). The send/receive work queues (WQ) are assigned to a consumer as a queue pair (QP). The messages can be sent over five different transport types: Reliable Connected (RC), Reliable datagram (RD), Unreliable Connected (UC), Unreliable Datagram (UD), and Raw Datagram (RawD). Consumers retrieve the results of these messages from a completion queue (CQ) through SAN send and receive work completions (WC). The source channel adapter takes care of segmenting outbound messages and sending them to the destination. The destination channel adapter takes care of reassembling inbound messages and placing them in the memory space designated by the destination's consumer. Two channel adapter types are present, a host channel adapter (HCA) and a target channel adapter (TCA). The host channel adapter is used by general purpose computing nodes to access the SAN fabric. Consumers use SAN verbs to access host channel adapter functions. The software that interprets verbs and directly accesses the channel adapter is known as the channel interface (CI).
Reliable Datagram Queue Pairs (RD QP's) rely on an underlying HCA facility to provide the reliability attributes. This underlying facility is the End-to-End Context (EEC). A mechanism is needed that provides for SAN RD QP's that can be associated with one or more EEC's at the local HCA and in the process remove the need to associate RD QP's to a specific partition.